The way I interpret it is that wording an agreement in terms of "we can delete whatever for whatever reason" doesn't specify in advance exactly what is fair game and what isn't. This is similar to Rossmann's complaints that NYC shouldn't get to fine a business for an alleged violation if they themselves cannot explain what the rules are in the first place.

So ideally if a video is to be taken down, it ought be under a rationale along the lines of "you agreed to not doing [very specific thing] and this video does it, therefore we took it down", not "technically by clicking on a link in our site, you agreed to fine print that says you'll sell us your soul, so suck it"